Do you know the exact dimensions and boundaries of your own property? While you might assume that you do, and even go so far as to build a fence, chances are that your fencing could be in the wrong place and you could have smaller or larger property than you thought.
A boundary survey can be conducted by licensed surveyors that can measure and determine the exact lines of your property. You boundary line can be determined by council and historical records combined with the current survey and previous legal land surveys.
If you are unsure of your boundary lines, find a professional to take a survey of your land. Not doing so could mean you have to move your fencing later on, or even demolish structures like gardens or buildings.
If you are building on new land or looking at rebuilding or adding extensions, then a land survey will most likely be mandatory anyway. Not only will a surveyor determine the edge of your property, but they will assess other risks to your property and the suitability of intended buildings on your land.